Engine pressure-equalizing valve.



C.G.STONEL ENGINE PRESSURE EQUALIZING VALVE. APPLICATION FILED AUG. 5, 1910.

1,004,493. Patented Sept; 26, 1911.

5 6 a 4'? 1 A4 QHHHIIIHIIIIIII UNITED STATES PATENT OFFICE:

following is a specification.

. The present invention is designed ta equalize the pressure at opposite ends of an engine cylinder without establishing co munication between the engine cylinder and the atmosphere, the mechanism being of such construction as to accomplish the desired result automatically-w hfiithe pressure within the cylinder is] sufficiently reduced from any cause.

The invention is particularly adapted for locomotive engines so as to equalize the pressure upon opposite sides oi the pistons when a partialvacuum is formedin one end of the cylinders from any cause. This result is accomplished. by means of the valve mechanismshown 1n the accompanying drawing,

which is a sectional view of a casing having passag opposite. ends of the cylinder of a locomotive f chamber 2' and are the chamber 2 and a cap plate .7 closes openings communicating with the passages 3 and 4.;Openings 8 are formed in the cap plate 6. Valve seats 9 and 10 are formed at the juncture of the passages 3 and 4 with the adaptedto be closed by 11- and 12 which open into d 4, A piston the chamber 2 means of valves the respective passages 3 a 13 is arranged to operate in and has the valves 11 and 12 connectedthereto by means of a fork 14, which is attached at a central and has its members orming stems to which the valves 11 and 12 are secured. It'will be understood that the piston-13 and the valves 11 and 12 move in unison.

- When the engine is inactive service the passages 3'. and 4 are 'connected to. opposite w nnernn rnnssunn-nouauzme vaLvn.

. Specification of-Letterslatent. rpaaa nmed August 5,1910. seriaimfswshpv; jg y I es which are 111 communication with establis gine cylin er and the atmosphere. The 1n oint tothe piston 13' -l' i -omnnns G.S'I.ONE, or 'NoR'rHBEssEi/rmt," lENNSiLVANIAI" Patented s nt-26 9. 1

' ends of they engine cylinder and when the latter is under pressure, as when the engine 1s 1n normal work ng condition, the pressure within the passages 3 and 4 serves to hold the valves 11 and 12 seated, thereby preventing communication between the passages 3 and 4 and opposite ends of the cylinder. \Vhen the pressure within one or the other end of the engine cylinder falls below a given pressure or a partial vacuum is created therein from any cause the pressure within the'passages 3-or 4 connected with said end of the cylinder is correspondingly reduced, with the result that the valve is drawn inward into such passage, thereby unseating both valves 11 and 12 and establishing communication between the two passages 3 and 4 through the inner ends of the chanfoer'2 and at the same time equalizing the pressure between opposite ends of the engine cylinder. When a partial vacuum is created within any one of the passages 3 or 4 the piston 13 moves inward with the valves 11 and 12 this being due to atmospheric pressure upon the outer side of the piston 13. It 'will be observed that the pressure between the passages 3, and 4 and opposite ends of the engine cylinder is equalized without in communication between the enstant the partial vacuum is overcome and the engine assumes "normal working conditionthe pressure within the passages 8 and 4 acting upon the inner. face of the piston 13 moves the latter outward in the chamber 2 and seats the valves 11 and 12 and the pressure acting upon said valves holds them seated until such time as an abnormal condition may exist when the valves 11 and 12 will again automatically unseat and admit of equalization of pressure between opposite ends of the engine cylinder.

From the fore oing description, taken in connection with t e accompanying drawing,

the advantages of the construction and of the method of operation will be readily apparent to those skilled in the art to which the invention appertains, andwhile I'have described the principle of operation of the invention, together with the device which I now consider to be the embodimentthereof, I desire to have it understood that the device shown is merely illustrative, and that such changes may be made when desired as are withm the scope. of the, claim' appended hereto. 1

It should be understood that the valves do not open and close with each stroke of the piston, but remain open as long as the pressure within the cylinder is below a given point and will remain closed so long as the pressure Within the cylinder is above a given point, thereby reducing the wear on the valves to a minimum amount.

Having thus described the invention what is claimed as new, is

A valve mechanism for the purposes specified comprising a casing having a chamber which is in communication at one end with the atmosphere and which has independent passages leading from its opposite end and in communication with oppositeends oft-he engine cylinder, said passages having valve seats at their juncture withthe chamberfaf seats upon outward movement of the piston in the chamber.

In testimony whereof I afiix my signature in presence of two witnesses.

-Witnesses:

HARRY Ar BRooKs,

H. B. Sronon'rom.

- CHARLES 'G. STONE. 

